Posthole digger attachment



Aprii 1949- H. B. ADAMS 2,468,319

POSTHOLE DIGGBR ATTACHMENT Filed Aug. 12. 1946 2 Sheets-Sheet 1 INVENTOR,

April 26, 1949. H. B. ADAMS POSTHOLE DIGGER ATTACHMENT Filed Aug. 12, 1946 2 Sheets-Sheet 2 Patented Apr. 26, 1949 UNl'lED STATES Parent orrlea POSTHOLE BIGGER ATTACHMENT Harold B. Adams, Kansas City, Mo. Application August 12, 1M6, Serial No. 689,983

3 Claims. ll

This invention relates to improvements in post hole digger attachment for tractors and has particular reference to a rotary type earth drilling auger, and is an improvement over my pending application, Ser. No. 574,493, filed January 25, 1945.

The principal object of the present invention is the provision of an earth drilling auger attachment for tractors that will automatically take a vertical position regardless of the contour of the ground on which the tractor is positioned.

Another object of the invention'is the provision of a post hole digging apparatus having a universally adjustable torque bar that eliminates substantially all twisting strains and binds and facilitates rapid digging.

Other objects are simplicity and sturdiness of construction, ease and accuracy of operation and adaptability for use on the various types of standard farm tractors.

With these objects in view, as well as other objects which will appear during the course of the specification, reference will be had to the drawings wherein:

Figure l is a side elevation of a post hole digger attachment for tractors embodying. this invention.

Fig. 2 is a plan View of the digger shown in Figure 1.

Fig. 3 is an enlarged plan view of a portion of the digger.

Fig. 4. is an enlarged elevational view of an outer portion of the apparatus with parts shown in section.

Fig. 5 is a fragmentary sectional view taken on line V-V of Figure 3.

Referring more in detail to the parts, the numeral lli designates a tractor, mounted on wheel 52 positioned on axle i l which is mounted on a differential housing it. Housing it, has spaced apart disc side plates it? which are secured to the tractor housing 283 by means of screws 22. A power take-oil shaft 26 driven in the usual manner by the tractor power unit extends from the rear of the tractor housing and is adapted to be omratively connected to drive associated equipment such as the present post hole digger.

The post hole digger attachment includes a substantially V-shaped frame or boom 26 comprising two side bars 26 joined to ether at their outer and upper extremities by means of a cross bar or headerplate 36 which is welded or otherwise attached thereto.

The lower extremitles of side bars are spaced apart and interconnected by cross bar 34 and by means of screws 22 serve to support the inner end of the boom to the tractor. Brace, bars it secured adjacent the outer extremities of side bars 28 respectively by bolts and at their inner ends to the difierential housing by means of screws 22 are disposed in angled relation to the side bars 28 to stabilize the boom and secure its outer end in fixed relation relative to the supporting tractor.

A Windlass ll comprising a drum I39 mounted on crank shaft 55 which in turn is rotatably mounted in bracket 53 attached to one of the side arms 28 by means of bolts 55. Drum 39 is provided with end flanges 5i and 58, and the outer flange 59 is ratchet toothed at Hi to engage a pawl 63 pivoted at 65 to bracket ti to support the drilling mechanism in a raised position. It will be noted that the Windlass is disposed off center to permit free movement of the drilling parts in their universal movement.

Extending horizontally and substantially perpendicular to the header plate 3%? is a trunnion 6?. which is rigidly carried by the boom.

A sheave housing 65 having spaced apart side walls til, a top wall 66 and a lower cross bar 6% bored at it to receive the trunnion 52 is prothe housing $5 is pivotally nion by cotter key 6?. A sheave wheel i2 is rotatably mounted on a pin it carried by side walls t l. Pin M is disposed at substantially a right angle to trunnion 52 and extends outwardly beyond side walls M to engage openings formed through cars it fixed to sleeve 8t whereby these parts are pivotally .joined together. Sleeve 80 is round in cross section and is adapted to receive a guide rod 82. Rod 82 extends downwardly below sleeve 89 and is adapted to fit into the upper plate 86 of transmission housing 88 to which it is securely attached by means of bolt 9d. The lower plate 92 of housing 88 is secured to plate 86 by means of bolts 9 3.

An opening 96 bored through the hub of. plate 92 is in axial alignment with guide rod 82 and is adapted to receive for rotation therein a stub shaft 98 to which is securely mounted an auger 3 shaft 98 on which is fixedly mounted the beveled gear wheel N16. The lower plate 92 of housing 88 is bored at 108 to rotatably receive shaft H carrying beveled pinion H2 which intermeshes with beveled gear HIE. A square drive shaft Ht interconnected to shaft H0 by means of a universal joint H6 extends through the squared portion I ID of the driving tube H20. This driving tube is connected with take-off shaft 24 by a universal joint I22. This mechanism is ,so constructed and operated as to drive the parts regardless of the vertical position of the gear housing 88 relative to the ground surface. Furthermore, the auger and associated parts may be universally tilted relative to the boom 26. A cable l 28 attached by means of bolt 90 to the gear housing extends over sheave wheel 12 thence over drum d'l to which it is securely attached at its extremity. When the parts are in position, as shown, with the pawl 93 engaging ratchet teeth ti the auger and associated parts will be maintained in the raised position. During the drilling operation as hereinafter described, the pawl 63 may be swung forwardly to disengage the ratchet teeth and the auger will be fed by gravity to contact the earth and then rotated by the powered tractor to bore the desired hole. It will be noted that the cable I28 is hitched to the gear housing at one side of the center thereof in order to support the driving rod and upper associated parts in such a way as to maintain the axis of the auger member in a substantially vertical position. The sheave wheel i2 is so positioned that the flanged edges thereof are spaced sufi'iciently close to the top wall 68 of the housing as to preclude any accidental dislodgment of the cable from the wheel. Since there is a tendency of the gear housing 88 to rotate during the drilling operation it has been found convenient to provide a torque bar Hill which is universally joined to one of the side bars 28 by a bracket 532 having an eye i3 3 which interconnects with an eye E36 formed integral with the inner end of the torque bar lit. This torque bar is of circular cross section and is slidably mounted in a, sleeve i313 having a stub shaft Mil extending diagonally therefrom which is pivotally mounted in plate M2 attached to a gear housing 88 by means of bolts 94.

It will be noted that this torque bar extends forwardly through sleeve I38 a suflicient distance to serve as an operating handle I44 whereby the operator may force the auger more forcefully into the earth's structure during the digging operation and may also raise the auger if and when it is found necessary. Due to the mounting of the torque bar I30 as described, the twisting strains and binds of the operating parts is substantially eliminated and the torque bar adds much rigidity and strength to the entire machine.

What I claimas new and desire to cover by Letters Patent is:

1. A tractor attachment for boring substantially perpendicular holes into the earth regardless of out of level position of the tractor on which'the attachment is adapted to be mounted including a boom, means for rigidly supporting the boom on a tractor to project outwardly therefrom, a pulley bracket, means pivotally mounting the pulley bracket on the boom for movement on a substantially horizontal axis, a guide. means for pivotally mounting the guide on the bracket for movement on a substantially horizontal axis drive housing, an auger carried by and depend ing from the drive housing, a rigid member fixed to and extending upwardly from the drive housing for slidable support in the guide, a Windlass having fixed support relative to the boom, a pulley rotatably carried on the pulley bracket, a flexible member operable on the pulley and having one end anchored with respect to the drive housing and having the other end connected with the Windlass for raising and lowering the auger relatively to the guide, means in the driving housing having driving connection with the auger and adapted for connection with a power takeofi of .the tractor to rotate the auger, and a torque member between the drive housing and boom for resisting rotation of the drive housing, said torque member having self-adjusting connections with the drive housing and said boom to cooperate with the guide in maintaining perpendicularity of the auger.

2. A tractor attachment for boring substantially perpendicular holes into the earth regardless of out of level position of the tractor on which the attachment is adapted to be mounted including a boom, means for rigidly supporting the boom on a tractor to project outwardly therefrom, a pulley bracket, means pivotally mounting the pulley bracket on the boom for movement on a substantially horizontal axis, a guide, means for pivotally mounting the guide on the bracket for movement on a substantially horizontal axis transverse to and vertically above the first named axis to cooperate with the first-named mounting means in maintaining perpendicularity of the uide, a drive housing, an auger carried by and depending from the drive housing, a rigid member fixed to and extending upwardly from the drive housing coaxially with said auger for slidable support in the guide, a Windlass having fixed support relative to the boom, a pulley rotatably carried on the pulley bracket coaxially with the pivotal axis of said guide, a flexible member op-. erable on the pulley and having one end anchored with respect to the drive housing and having the other end connected with the windlass for raising and lowering the auger relatively to the guide, means in the drive housing having driving connection with the auger and adapted for connection with a power take ofi of the tractor to rotate the auger, and a torque member between the drive housing and boom for resisting rotation of the drive housing, said torque member having self-adjusting connections with the drive housing and said boom to cooperate with the guide in maintaining perpendicularity of the auger.

3. A tractor attachment for boring substantially perpendicular holes into the earth regard less of out of level position of the tractor on which the attachment is adapted to be mounted including a boom, means for rigidly supporting the boom on a tractor to project outwardly therefrom, a pulley bracket, means pivotally mount ing the pulley bracket on the boom for movement on a substantially horizontal axis, a guide, means for pivotally mounting the guide on the bracket for movement on a substantially horizontal axis transverse to and vertically above the first named axis to cooperate with the first-named mounting means in maintaining perpendicularity of the guide, a drive housing, an augercarried by and depending from the drive housing, a rigid member fixed to and extending upwardly from the drive housing coaxially with said auger for slidable support in the guide, a Windlass having fixed support relative to the boom, a pulley rotatably carried on the pulley bracket coaxially with the pivotal axis of said guide, a flexible member operable on the pulley and having one end anchored with respect to the drive housing and having the other end connected with the Windlass for raising and lowering the auger relatively to the guide, means in the drive housing having driving connection with the auger and adapted for connection with a power takeoff of the tractor to rotate the auger, a, torque member between the drive housing and boom for resisting rotation of the drive housing, a guide pivotally connected to said drive housing and slidably supporting said torque member, and a ring fixed to the opposite end of said torque member and adapted to engage loosely a ring fixed to said boom for universally connecting said torque member to said boom.

HAROLD B. ADAMS.

6 REFERENCES CITED The following references are of record in the file of this patent:

' UNITED STATES PATENTS Number Name Date 1,507,776 Humiston Sept. 9, 1924 1,557,635 Ware, Jr. Oct. 20, 1925 1,641,926 Genug Sept. 6, 1927 1,971,922 Smith Aug. 28, 1934 1,999,115 Shinn Apr. 23, 1935 2,081,200 Hollingsworth May 25, 1937 2,321,680 Houston June 15, 1943 2,410,508 Lamme Nov. 5, 1946 

